The explosions were Big textured particles, with each particle rotation following the direction tangent,
(to effectively lose the "textured balls" feel)
and with the firey procedural texture animation speed based on the "heat" property from EmFluid effect,
making the 'hotter' particle's texture develop faster, and then slow down as they 'cool'.

Though it was hard to make them fade-out gracefully, some particles would pop-out of existence near the end of their lifetimes, it was nothing that couldn't easily be fixed.